Patent · US Expired

Dynamic braking of direct current motors

US4092577A · kind A · utility

11Cited by
4References
9Claims
0Family size

Assignee

Inventor

Key dates

Filing dateFeb 16, 1977
Grant dateMay 30, 1978
Priority date
Expiry dateFeb 16, 1997

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02T10/64
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A braking system for, primarily, separately excited D.C. traction motors, in which rheostatic braking is effected by field reversal to generate armature current freewheeling through the low impedance supply and through a brake resistor in series with the armature. A contactor shorts out the brake resistor for normal motoring. Field excitation in conjunction with armature current or armature voltage polarity reversal is detected to indicate the motor generating function, lock open the motoring contactor and prevent short circuiting of the motor/generator. Plug braking by energisation of the armature supply is thus always permissible either by brake handle and power handle or reverse handle and power handle. The armature current then contains a rheostatic braking component and a tractor braking component. What would normally be mis-use of the reversing control to achieve rapid deceleration thus becomes acceptable.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.